The statements in this section merely provide background information related to the present invention and may or may not constitute prior art.
It is known that heat treatment apparatuses (also referred as prebaking machine) are used to prebake the resist coated on a substrate in the photolithography process for manufacturing a semiconductor device such as LCD modules and semiconductor chips. The heat treatment apparatus can prebake the resist coated on the substrate preliminary so as to evaporate the solvent for the resist and enhance the adhesion of the resist. The heat treatment apparatus used in prebaking unit usually comprises a heat source, and a hot plate or a cold plate. The hot plate serves to heat the substrate to 50˜130° C., the cold plate serves to cool the substrate to ambient temperature. The heat source transfer heat to the hot plate or the cold plate, so as to heat or cool the substrate mounted on the hot plate or the cold plate. In tradition, there is only a heat source; and the heat treatment temperature can not varied from one temperature to another temperature.